Before the most recent update the endermite attracted the endermen. This, I had used to create an ender xp farm. As of the update, the endermen are no longer attracted to the endermite. Not sure if this is a bug or a change that Mojang wanted to make so thought that it might be useful to just say since it's not on any change list which I have seen thus far.
Linked issues
is duplicated by 77
Comments 18
I can confirm this happens
This is still an issue in 14w18a
Yes, confirmed for 14w18a
Still an issue in 14w18b
I can confirm for 1.16.1. It happenned to me when I was testing and making an endermen farm
Confirmed/Reproduced in 20w28a.
Is there any way to bypass this, because I was having the same error.

Give the endermite the "PlayerSpawned:1b" tag.
I am using 1.16.5 and this bug is still happening to me. Whenever I spawn an endermite, the enderman do not attack it.
Also noticed this while checking out the new endermite model. Tested in Creative and Spectator modes, in the overworld and in the End. Endermen, both from spawn eggs and natural spawn, ignored spawn egg endermites. Unsure about naturally spawned ones.